6-氯嘌呤与人血清白蛋白的相互作用及分析应用

6-Chloropurine interactions with human serum albumin and its application analysis

在模拟生理条件下,运用荧光光谱和分子对接方法研究了核苷衍生物6-氯嘌呤(6-CP)与人血清白蛋白(HSA)的相互作用.结果表明,6-CP对HSA内源荧光的猝灭类型为形成复合物的静态猝灭,通过热力学参数确定6-CP与HSA之间存在氢键和范德华力,分子对接结果也证明了氢键和疏水作用力的存在.三维荧光光谱研究了6-CP对HSA构象的影响,并以华法令和布洛芬为分子探针进行竞争实验.在此基础上,以6-CP为分子探针,运用固定波长同步荧光光谱法测定了生物样品中的蛋白质含量.在最佳实验条件下,对11份空白溶液进行平行测定,检测限达到0.511 mg/L,相对标准偏差为0.324%.运用此方法对血清、唾液进行了加标回收实验.

The binding of 6-chloropurine（6-CP） with human serum albumin（HSA） was investigated by fluorescence spectroscopy and molecular modeling under simulated physiological conditions,which results showed that 6-CP formed a complex with HSA and strongly quenched the intrinsic fluorescence of HSA through static quenching.The change in enthalpy（H） and entropy（S） were calculated by the van’t Hoff equation.These data suggested that there were hydrogen bonds and van der Waals forces between 6-CP and HSA.These results agreed with those obtained by molecular modeling,which also showed hydrophobic interactions between HSA and 6-CP.The effect of 6-CP on the conformation of HSA was analyzed by three-dimensional fluorescence spectroscopy,and Warfarin and Ibuprofen were used as molecular probes to investigate the interaction sites of 6-CP and HSA.Under the optimum conditions,based on that the synchronous fluorescence intensity（I SF） of the system was in direct proportion to the concentration of protein,the method of determining the protein used 6-CP as a fluorescence probe was applied with the detection limit 0.511 mg/L.And the amount of the proteins in human serum and saliva samples were detected and the recovery was 97.1%~101%.This method is simple,rapid,high sensitivity and could be used in biochemistry,clinical diagnosis or quality inspection.